A late-night talk show is a subgenre of the talk show genre. It is specifically a kind of comedy-oriented talk and variety show that airs late at night. Characteristics of the genre include topical monologues in which the host makes fun of the day's news, comedy sketches, celebrity interviews, and musical performances primarily by new and current artists signed to a major record label. The late-night talk show format was popularized, though not invented, by Johnny Carson with The Tonight Show Starring Johnny Carson on NBC. Often late-night talk shows feature a desk, behind which the host sits to interview guests. Many late night talk shows feature a house band which generally performs cover songs for the studio audience during commercial breaks & occasionally will back up a guest artist.

Late-night talk shows are a popular format in the United States, but are not as prominent in other parts of the world. Shows that loosely resemble the format air in other countries, but generally air weekly as opposed to the nightly airings of those in the United States. They also generally air in time slots considered to be prime time in the United States.

Late-night talk shows had their genesis in early variety shows, a format that migrated to television from radio, where it had been the dominant form of light entertainment during most of the old-time radio era. Early television variety shows included The Ed Sullivan Show (originally known as Toast of the Town), which aired on CBS Sunday nights from 1948 to 1971 and was hosted by Ed Sullivan, and Texaco Star Theater with Milton Berle, which aired on NBC from 1948 to 1956. These shows aired once a week in evening time slots that would come to be known as prime time. The first show to air in a late night time slot itself, Broadway Open House, aired on NBC in 1950 and was canceled a year later; not enough people owned television sets to make a late-night television series worthwhile. The first version of The Tonight Show, Tonight Starring Steve Allen, debuted in 1954 on NBC. The show created many modern talk show staples included an opening monologue, celebrity interviews, audience participation, comedy bits, and musical performances. By this point, the Federal Communications Commission had lifted a freeze on new television stations, which allowed new stations to pop up across the country, and television adoption soon grew exponentially. As a result, unlike Broadway Open House, Tonight proved to be a resounding success.

The success of the show led Allen to get another show, entitled The Steve Allen Show, which would compete with The Ed Sullivan Show on Sunday nights. Meanwhile, hosting duties of The Tonight Show were split between Allen and Ernie Kovacs; Kovacs had defected to NBC from his own late-night show on the then-crumbling DuMont Television Network. Both Allen and Kovacs departed from Tonight in 1957 in order to focus on Allen's Sunday night show. After the two left, the format changed similar to that of Today and was renamed Tonight! America After Dark and was hosted first by Jack Lescoulie and then by Al Collins while interviews were performed by Hy Gardner, and a house band led by Lou Stein. The show was not popular leading to many NBC affiliates dropping the show. The show returned to the original format that year and was renamed Tonight Starring Jack Paar, with Jack Paar assuming hosting duties. The even greater success of the show during Paar's hosting resulted in many NBC affiliates re-airing the show. Paar introduced another talk show staple, the idea of guest hosts, and his regular guest host was Johnny Carson, who would go on to replace Paar as host of The Tonight Show in 1962. Paar also engaged in a feud with radio host Walter Winchell as well as Ed Sullivan, the feud which indirectly ended Winchell's career. Paar left the show in 1962 citing the reason that he could not handle the work load of The Tonight Show (at the time, the show ran 105 minutes a day, five days a week).

NBC's two other rivals during the early television era, CBS and ABC, did not attempt any major forays into late-night television until the 1960s. ABC's first effort at late-night TV was hosted by Les Crane, which pioneered the controversial tabloid talk show format that would not become popular until two decades later. Crane's show lasted only six months. Shorter still was The Las Vegas Show, a Las Vegas-based late-night show hosted by Bill Dana that was the only offering of the United Network that ever made it to air (because that network only had a handful of affiliates, it also syndicated to CBS, ABC and independent stations); it, along with the network, only lasted five weeks in summer 1967. Steve Allen himself returned to late-night in syndication twice in this time frame, first with a show that ran from 1962 to 1964 and then with a series that ran from 1968 to 1971. CBS went without late-night TV until 1969, when it acquired The Merv Griffin Show from syndication. By this point, NBC had already cornered the market for late-night television viewing and would go on to dominate the ratings for several decades.

A nationwide prohibition on tobacco advertising prompted NBC to extend its broadcast day by an additional hour with a low-cost overnight talk show it hoped would recuperate some of that lost revenue.[1] In 1973, NBC launched The Tomorrow Show hosted by Tom Snyder immediately following Carson's Tonight Show at 1:00 a.m. ET. The show was different from The Tonight Show. For instance, the show featured no studio audience, while Snyder would conduct one-on-one interviews (Snyder's guest list was often more eclectic and would sometimes include the intellectuals that Carson had long since abandoned) with a cigarette in hand. After NBC forcibly changed the show's format and added gossip reporter Rona Barrett as a co-host, Snyder quit the show at the end of 1981, leading to its cancellation. NBC then signed on Late Night with David Letterman, which aired immediately following a now shorter Tonight. During his tenure as host of The Tonight Show, Carson became known as The King of Late Night. While numerous hosts (Merv Griffin and Dick Cavett being the best-known) attempted to compete with Carson, none was ever successful in drawing more viewers than Carson did on Tonight. Much like Paar, Carson became tired of fulfilling the workload of 525 minutes a week, so as local newscasts expanded, The Tonight Show was shortened to 90 minutes and again to 60 minutes by 1982. Because of a lack of competition, Carson was free to take time off (Carson, by 1982, was only hosting three new shows a week) and invite guest hosts to host the show on a weekly basis, including Joey Bishop, Joan Rivers, David Letterman, Bob Newhart, Jay Leno and Jerry Lewis.

Throughout the 1980s, Rivers served as Carson's permanent guest host. Many in 1986, including top executives at NBC, thought it was possible that Johnny Carson would retire after reaching his 25th anniversary on October 1, 1987, as it was such a logical cut-off point. In the spring of 1986, a confidential memo between top NBC executives listing about ten possible replacements in the event of Carson's retirement the next year was leaked. When Rivers saw it, she was shocked to see that she was nowhere on the list despite the fact that she had been The Tonight Show '​s permanent guest host since 1983. In 1986, Joan Rivers joined the brand new Fox network, where she would host her own late night talk show, The Late Show which competed directly against The Tonight Show. Clint Holmes served as Rivers' announcer while Mark Hudson served as bandleader. Because of this, Carson was incensed never spoke to Rivers again. Carson did not retire in 1987, instead continuing as host until 1992. Rivers left The Late Show in 1987 after abysmal ratings and a battle with network executives, leading her to be replaced by Arsenio Hall. Hall performed extremely well in the 18–49 demographic, however Fox had already greenlit The Wilton North Report to replace The Late Show, leading to Hall hosting his own late night talk show in syndication after The Late Show was cancelled in 1988. The Late Show continued with many unknown hosts until its cancellation. Hall's syndicated show, The Arsenio Hall Show, began in syndication in 1988, becoming more popular among younger viewers than Carson. The last network attempt at a Carson competitor, CBS's The Pat Sajak Show, lasted less than sixteen months, debuting in 1989 and being cancelled in 1990. ABC opted not to compete against Carson with a late night talk show, instead counterprogramming with a successful news magazine entitled Nightline beginning in 1980.

Carson retired as host of The Tonight Show in 1992 following his 30th anniversary as host. This garnered major media attention and speculation on who would replace Carson. The two candidates were David Letterman (host of Late Night since 1982) and Jay Leno (Carson's regular guest host since 1987). Leno was eventually chosen, leading to Letterman leaving the network to launch his own late night talk show, the Late Show with David Letterman on CBS in 1993. The Tonight Show with Jay Leno debuted in 1992. Letterman was replaced by newcomer Conan O'Brien as host of Late Night. Arsenio Hall's show lost numerous affiliates after Letterman's debut and his show was canceled one year later. Fox returned to late night television in September 1993 with The Chevy Chase Show hosted by Saturday Night Live alumnus Chevy Chase. However, due to sagging ratings and disastrous reviews, the show was cancelled the following month. Even MTV entered the late night contest when it debuted The Jon Stewart Show, hosted by Jon Stewart, which ran until 1995. Letterman initially won the late night ratings battle but fell behind Leno in 1995; Leno generally remained in first place until first leaving Tonight in 2009. To combat NBC's Late Night, David Letterman created The Late Late Show to follow Letterman at 12:37; the first host was former host of The Tomorrow Show Tom Snyder, who hosted the show using the same format he had used on Tomorrow until his departure in 1999. The Late Late Show's second host, Craig Kilborn, followed a more conventional (albeit low-budget) late-night format; had previously served as host of The Daily Show, a late night satirical news program on Comedy Central, and upon Kilborn's departure, Jon Stewart replaced him on that show. Perhaps one of the most unusual late night hosts to come out of this boom was basketball player and later entrepreneur Magic Johnson, whose syndicated The Magic Hour was a major flop and effectively ended any future efforts at a syndicated late-night talk show at that point in time.

ABC finally re-entered the late night comedy fray in 1997 by installing Politically Incorrect with Bill Maher (which had aired on Comedy Central from 1993 to 1996) into its lineup after Nightline. Unlike traditional late night talk shows, Politically Incorrect was a half-hour in length, and (following a brief host monologue) featured a panel of four guests debating topical issues while Maher moderated in a comedic fashion.

Politically Incorrect was canceled due to low ratings in the summer of 2002, after which Maher joined HBO and began hosting the similarly formatted weekly series Real Time. ABC then tapped Comedy Central personality Jimmy Kimmel to host his own late night talk show (in a more traditional format) and named it Jimmy Kimmel Live!. From its beginning in 2003 until early 2013, the show aired behind Nightline in ABC's nightly lineup. In early 2013, ABC promoted Jimmy Kimmel Live! to the 11:35pm slot, while Nightline was relegated to 12:35am.

Jake Sasseville entered the late night arena after a self-syndication campaign got him clearance on several ABC affiliates by local general managers in 2008. The Edge with Jake Sasseville aired after Jimmy Kimmel Live! in markets reaching a total of 35 million homes, despite the network's concerns.[2] The show went off the air in 2010. Another syndicated show that earned significant clearance in the late 2000s was Comics Unleashed, a panel comedy show that lasted only one season but ran in reruns for several years afterward.

It was announced on July 21, 2008 that Jay Leno would host his final episode of The Tonight Show on May 29, 2009 with Conan O'Brien and James Taylor as his guests.[6] O'Brien took over hosting duties the following Monday, June 1, 2009. On December 9, 2008, it was announced that Jay Leno would be hosting a new nightly prime time show in September 2009, which aired at 10 p.m. ET. The Jay Leno Show ended after a short run on February 9, 2010, due to low ratings, which, combined with NBC's poor prime-time performance at the time, affected viewership of its lead-out late newscasts on many NBC stations.[7]

On January 7, 2010, multiple media outlets reported that The Jay Leno Show would be moved from the 10 p.m. Eastern time slot to 11:35 p.m. and The Tonight Show with Conan O'Brien would be moved from 11:35 p.m. to 12:05 a.m. effective March 1, 2010, the first time in its history that the show would begin after midnight.[8][9][10] On January 12, 2010, O'Brien publicly announced in an open letter that he intended to leave NBC if they moved The Tonight Show to anytime after midnight in order to accommodate moving The Jay Leno Show to 11:35 p.m. ET. He felt it would damage the show's legacy as it always started after the late local news since it began in 1954.[11] After several days of negotiations, O'Brien reached a settlement with NBC that allowed him to leave The Tonight Show on January 22, 2010, ending his partnership with NBC after 22 years.[12] Leno began his second tenure as host of The Tonight Show on March 1, 2010, after the 2010 Winter Olympics, but only after major controversy.[13] Leno's second Tonight was taped at NBC's Studio 11 in Burbank, the former home of The Jay Leno Show, with a modified version of that show's set. After leaving NBC, O'Brien began hosting his own late night talk show, Conan, on TBS on November 8, 2010, after his non-compete clause had lapsed.

In March 2013, news broke that NBC was expected to part ways with Leno for good after his contract expired in 2014, clearing the way for Fallon (whose tenure at Late Night had found success with a young, culturally savvy audience) to take over The Tonight Show beginning that year, which also marked the 60th anniversary of franchise. NBC confirmed the change on April 3, 2013. Under Fallon, the show returned to New York City, where the show originated from its 1954 debut until 1972; NBC no longer owns the former company-owned studios in Burbank where Carson and Leno's programs originated (O'Brien's Tonight Show taped at nearby Universal Studios). On May 13, 2013, it was announced that Fallon's former SNL castmate Seth Meyers would take over as host of Late Night once Fallon took over The Tonight Show.[14]The Tonight Show Starring Jimmy Fallon debuted during NBC's coverage of the Winter Olympics in Russia on February 17, 2014, while Late Night with Seth Meyers debuted one week later.

David Letterman's contract with CBS expires in 2015, after which he intends to retire;[15]Late Show bandleader and sidekick Paul Shaffer made public his intent to retire at the end of the previous contract, which ended in 2014,[16] but had also stated he will stay on with the show if asked (and subsequently has done so).[17] Letterman will be succeeded by Stephen Colbert, who had hosted Comedy Central's The Colbert Report since 2005.[18] Craig Ferguson retired from late night on December 19, 2014.;[19] on September 8, 2014, British comedian James Corden was announced as the new host of The Late Late Show beginning in 2015.[20]

Jon Stewart's contract with Comedy Central also expires in 2015, at which point Stewart will retire.[21]

^http://news.bbc.co.uk/2/hi/8450575.stm "This diet of TV late at night is a key reason up to 40% of Americans get less than the "recommended" seven to eight hours of sleep, according to recent research from the University of Pennsylvania."